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Client Connection to RAC Intermittently Fails-ORA-12545 TNS: Host or Object Does not Exist (Doc ID 364855.1)

Last updated on MARCH 31, 2022

Applies to:

Oracle Net Services - Version and later
Oracle Database - Enterprise Edition - Version and later
Information in this document applies to any platform.


When attempting to connect to a RAC service name, the connection  intermittently  fails with an ORA-12545 error:  TNS: Host or object doesn't exist.   The expected behavior is that the connection would be redirected to any of the VIP listeners in the cluster.  This is normal under RAC Cluster node load balancing. 

However, when the server side listener endpoints are not correctly configured OR the client cannot resolve all forms of the VIP hostname, this connect-time issue can arise.


This is likely a new installation of RAC cluster.


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